556561 has 4 divisors (see below), whose sum is σ = 558900. Its totient is φ = 554224.

The previous prime is 556559. The next prime is 556573. The reversal of 556561 is 165655.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 59536 + 497025 = 244^2 + 705^2 .

It is a cyclic number.

It is not a de Polignac number, because 556561 - 2¹ = 556559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (556261) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 766 + ... + 1303.

It is an arithmetic number, because the mean of its divisors is an integer number (139725).

2⁵⁵⁶⁵⁶¹ is an apocalyptic number.

It is an amenable number.

556561 is a deficient number, since it is larger than the sum of its proper divisors (2339).

556561 is a wasteful number, since it uses less digits than its factorization.

556561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2338.

The product of its digits is 4500, while the sum is 28.

The square root of 556561 is about 746.0301602482. The cubic root of 556561 is about 82.2566320413.

The spelling of 556561 in words is "five hundred fifty-six thousand, five hundred sixty-one".